The invention relates to a method of producing a diode matrix, constructed in the form of a plug-in circuit board, for character generators, particularly for the code generator of electronic teleprinters or for a circuit board with optionally differing conductor configurations.
Character generators are employed in connection with the transmission of individual or groups of teleprinter characters in the teleprinter circuit technique and the like. For example, consecutive number generators are known which automatically transmit specific teleprinter characters before every message. Mechanical character generators were initially employed, which have long since been superseded by electronic character generators. Such general type of electronic character generator is illustrated in the book "Fernschreib-Vermittlungs-technik" by Rossberg/Korta, 1959, page 228. A diode matrix is provided in connection with the production of the characters, at the inputs of which are supplied the output signals of a ring counter which possesses as many stages as the number of elements possessed by the characters involved. Identical elements of all the characters appear simultaneously at the outputs of the diode matrix. While the name or code generators of teleprinters, on the other hand, have heretofore been a mechanical design, future electronic teleprinters will likewise require electronic code generators, as mechanical code generators occupy too much space, require too much power and generate too much noise, as well as presenting difficulties in connection with interference suppression. Furthermore, in such case the cost of mechanical code generators becomes excessive.
A diode matrix can be utilized to construct not only character generators, such as above referred to, but also code generators or so-called variant generators which are required, for example, for setting the keyboard type (full or narrow), the line spacing or the operational speed, and for signalling the end of the paper, or automatic "carriage return." In this application such a diode matrix can be interrogated by means of devices which are available in an electronic teleprinter. The diode matrix of a code generator must comply with various requirements. First, 20 freely selectable characters must be capable of production. Second, such characters must be capable of basic transmission in the five-element code or in the eight-element code. In addition, the diode matrix must be readily exchangeable when substitute machines are to be employed, must be able to be set at the characters to be transmitted by the customer service, or by the administrative service, without the use of special tools, and also must be capable of correction of the setting in the event of errors during the programming of the matrix.
It is also possible to construct a diode matrix utilizing the known screw diodes which are screwed vertically into a circuit board of appropriate construction at desired conductor intersection points. However, in this case only the number of diodes absolutely necessary for the desired functions are employed. It will be appreciated that both such diodes and the requisite construction required therefor are relatively expensive with the insertion of the diodes requiring a special tool and the time outlay for effecting programming being relatively great.
It is also possible to construct a matrix by the utilization of a crossbar distributor and commercially available diode plugs. In this case, while the time outlay for the programming is considerably less, a special tool is again required for handling the very small diode plugs.